1. Field of the Invention
The present invention relates to a liquid ink for ink jet having excellent ejection property and an ink jet recording method using the ink.
2. Description of the Related Art
An ink jet recording method is a recording method of applying a small ink droplet to any one of plain paper or glossy media to form an image, and has become rapidly widespread owing to reduction in costs and improvement in recording speed. In addition to improvement in the quality of images, as digital cameras has rapidly come into wide use, the method has been generally used as a method of outputting photographic images comparable to silver halide photographs.
In recent years, image quality has undergone improvement more than ever owing to, for example, extreme reduction in size of an ink droplet and an improvement of the color gamut involved in the introduction of multi-color inks. On the other hand, there have been additionally strict requests for not only the fastness properties of a formed image such as color development property, light resistance, and ozone resistance but also reliability such as ejection stability when the method is applied to a recording apparatus.
For example, an ink containing a phthalocyanine compound having a specific structure has been disclosed as an ink for providing an image excellent in fastness properties such as the ozone resistance (see Japanese Patent No. 2942319). An ink containing a monoazo compound having a specific structure has been also disclosed as an ink for providing an image having high chroma and high light resistance (see Japanese Patent Application Laid-Open No. 2002-504613).
However, with the advent of the recent miniaturization of an ink ejection portion in association with an improvement in quality of a recorded image, investigation has been conducted for additional improvements in reliability such as the ejection stability as well as in those properties mentioned above.
An ink for ink jet containing water as an aqueous medium, a water-insoluble coloring material, a resinous dispersant for dispersing the water-insoluble coloring material in the aqueous medium, glycerin, ethylene urea, and polyoxyethylene alkyl ether with an HLB of 13 or more has been disclosed as means for improving the ejection stability (see Japanese Patent Application Laid-Open No. 2003-138186). However, it is essential for the ink disclosed in the document to contain a pigment as a coloring material, and the document has no description concerning a use of a dye.